US12429885B2 - Method for adjusting aircraft controls - Google Patents

Method for adjusting aircraft controls

Info

Publication number
US12429885B2
US12429885B2 US18/455,884 US202318455884A US12429885B2 US 12429885 B2 US12429885 B2 US 12429885B2 US 202318455884 A US202318455884 A US 202318455884A US 12429885 B2 US12429885 B2 US 12429885B2
Authority
US
United States
Prior art keywords
aircraft
wind
control surfaces
flight control
flight
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active, expires
Application number
US18/455,884
Other versions
US20240077889A1 (en
Inventor
Stéphane Delannoy
José TORRALBA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Airbus Operations SAS
Original Assignee
Airbus Operations SAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Airbus Operations SAS filed Critical Airbus Operations SAS
Publication of US20240077889A1 publication Critical patent/US20240077889A1/en
Assigned to AIRBUS OPERATIONS SAS reassignment AIRBUS OPERATIONS SAS ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: TORRALBA, José, DELLANOY, STÉPHANE
Application granted granted Critical
Publication of US12429885B2 publication Critical patent/US12429885B2/en
Active legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/60Intended control result
    • G05D1/606Compensating for or utilising external environmental conditions, e.g. wind or water currents
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/08Control of attitude, i.e. control of roll, pitch, or yaw
    • G05D1/0808Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft
    • G05D1/0816Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft to ensure stability
    • G05D1/0833Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft to ensure stability using limited authority control
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C13/00Control systems or transmitting systems for actuating flying-control surfaces, lift-increasing flaps, air brakes, or spoilers
    • B64C13/02Initiating means
    • B64C13/16Initiating means actuated automatically, e.g. responsive to gust detectors
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/40Control within particular dimensions
    • G05D1/49Control of attitude, i.e. control of roll, pitch or yaw
    • G05D1/495Control of attitude, i.e. control of roll, pitch or yaw to ensure stability
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/60Intended control result
    • G05D1/646Following a predefined trajectory, e.g. a line marked on the floor or a flight path
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D2109/00Types of controlled vehicles
    • G05D2109/20Aircraft, e.g. drones
    • G05D2109/22Aircraft, e.g. drones with fixed wings

Definitions

  • the present invention relates to the field of the adjustment of aircraft controls in order to take into account an impact of wind on the aircraft in flight.
  • a method for controlling the flight control surfaces of an aircraft the method being implemented by a system for controlling the flight control surfaces of the aircraft in the form of electronic circuitry and comprising the following steps: obtaining a control law for the flight control surfaces ui as a function of flight controls of the aircraft; obtaining measurements of ground speed VGND of the aircraft, of true speed VTAS of the aircraft, of roll angle ⁇ of the aircraft, of pitch angle ⁇ of the aircraft, of angle of attack ⁇ of the aircraft, of sideslip angle ⁇ of the aircraft, and of slope angle ⁇ of the aircraft; performing an estimation of the wind V in three dimensions using the measurements obtained; performing an adjustment of the control law for the flight control surfaces ui, in order to counter the estimated effect of the wind, and thus obtain an adjusted control law for the flight control surfaces ua, by adding, to the control law for the flight control surfaces ui, a term for compensation of the wind uw comprising a term proportional to the derivative ⁇ dot over (V) ⁇ of the wind estimation
  • the adjusted control law for the flight control surfaces ua is obtained by further adding, to the control law for the flight control surfaces ui, a term proportional to the integral of the derivative ⁇ dot over (V) ⁇ of the wind estimation V.
  • K i is a multiplier coefficient of the term proportional to the integral of the derivative ⁇ dot over (V) ⁇ of the wind estimation V
  • K is a multiplier coefficient of the term proportional to the derivative ⁇ dot over (V) ⁇ of the wind estimation V
  • K d is a multiplier coefficient of the term proportional to the second derivative ⁇ umlaut over (V) ⁇ of the wind estimation V.
  • a system for controlling flight control surfaces of an aircraft is also provided in the form of electronic circuitry configured for implementing the following steps: obtaining a control law for the flight control surfaces ui as a function of flight controls of the aircraft; obtaining measurements of ground speed VGND of the aircraft, of true speed VTAS of the aircraft, of roll angle ⁇ of the aircraft, of pitch angle ⁇ of the aircraft, of angle of attack ⁇ of the aircraft, of sideslip angle ⁇ of the aircraft, and of slope angle ⁇ of the aircraft; performing an estimation of the wind V in three dimensions using the measurements obtained; performing an adjustment of the control law for the flight control surfaces ui, in order to counter the effect of the estimated wind, and thus to obtain an adjusted control law for the flight control surfaces ua, by adding, to the control law for the flight control surfaces ui, a term for compensation of the wind uw comprising a term proportional to the derivative ⁇ dot over (V) ⁇ of the wind estimation V; and controlling the aircraft by applying the adjusted control law ua.
  • An aircraft comprising a control system for flight control surfaces such as described hereinabove.
  • FIG. 1 illustrates schematically, as a top view, an aircraft equipped with a system for controlling the flight control surfaces of the aircraft comprising a sub-system for adjusting a control law of the aircraft;
  • FIG. 3 illustrates schematically one example of a hardware platform designed and configured for implementing the sub-system for adjusting a control law of the aircraft.
  • FIG. 1 thus illustrates schematically, as a top view, an aircraft 10 .
  • the aircraft 10 comprises a system 100 for controlling the flight control surfaces of the aircraft 10 (elevators, ailerons, rudder).
  • the system 100 applies a control law for the flight control surfaces (deflection commands) of the aircraft 10 as a function of flight controls of the aircraft 10 .
  • the system 100 for controlling the flight control surfaces of the aircraft 10 comprises a sub-system 101 for adjusting the control law of the aircraft 10 as a function of an estimation of the wind to which the aircraft 10 is subjected in flight.
  • the aircraft 10 comprises sensors (not shown in FIG. 1 ) and electronic control circuitry, designed and configured for supplying measurements of speed and of orientation of the aircraft 10 .
  • the sub-system 101 for adjusting the control law of the aircraft 10 is able to carry out an estimation of the wind in three dimensions, in a right orthonormal reference frame (xb, yb, zb) fixed with respect to the center of gravity of the aircraft 10 (with xb oriented towards the front of the aircraft 10 and yb oriented towards the left of the aircraft 10 ), in the following manner:
  • V [ - V GND ⁇ tan ⁇ ( ⁇ ) - V TAS ( sin ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) - cos ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ sin ⁇ ( ⁇ ) - sin ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ sin ⁇ ( ⁇ ) ) ) ) V GND ⁇ tan ⁇ ( ⁇ ) - V TAS ( sin ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) - cos ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ sin ⁇ ( ⁇ ) + sin ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ) ⁇ sin ⁇ ( ) + sin ⁇ ( ⁇
  • the sub-system 101 for adjusting the control law of the aircraft 10 comprises electronic circuitry designed and configured for carrying out a real-time estimation of the wind such as expressed hereinabove, in order to adjust a control law for flight control surfaces so as to reduce the impact of the wind on the aircraft 10 .
  • FIG. 2 illustrates schematically a method for controlling the aircraft 10 in flight aimed at reducing the impact of the wind on the aircraft 10 .
  • a step 201 the system 100 for controlling the flight control surfaces of the aircraft 10 obtains a control law for the flight control surfaces ui as a function of flight controls of the aircraft 10 .
  • the flight controls are actuated by the pilot, or by an autopilot system, for maneuvering the aircraft 10 in flight.
  • the control law for the flight control surfaces ui, obtained at the step 201 does not take into account the estimation of the wind.
  • the system 100 for controlling the flight control surfaces of the aircraft 10 obtains measurements of speed and of orientation of the aircraft 10 useful for the estimation of the wind, in real time. More particularly, the system 100 for controlling the flight control surfaces of the aircraft 10 obtains measurements of the ground speed VGND and of the true speed VTAS. The system 100 for controlling the flight control surfaces of the aircraft 10 further obtains the roll angle ⁇ and the pitch angle ⁇ , together with the angle of attack ⁇ , the sideslip angle ⁇ and the slope angle ⁇ .
  • the sub-system 101 for adjusting the control law of the aircraft 10 carries out an estimation of the wind, as already described hereinabove.
  • the sub-system 101 for adjusting the control law of the aircraft 10 tracks the estimation of the wind over time.
  • the sub-system 101 for adjusting the control law of the aircraft 10 carries out an adjustment of the control law for the flight control surfaces ui obtained at the step 201 , in order to counter the effect of the wind such as estimated at the step 203 , and thus obtains an adjusted control law for the flight control surfaces ua.
  • K is a predetermined coefficient
  • K i is a predetermined coefficient
  • K d is a predetermined coefficient
  • the aircraft 10 is modelled by a representation of states defined, for a non-rigid aircraft aero-elastic model (taking into account elastic deformations due to the coupling between structural modes and aerodynamic forces), by:
  • the new state ⁇ dot over (x) ⁇ of the aircraft 10 obtained by applying the control law for the flight control surfaces ui depends on the current state x of the aircraft 10 and on the control law for the flight control surfaces ui.
  • the new state ⁇ dot over (x) ⁇ of the aircraft 10 associated with the compensation term uw depends on the current state x of the aircraft 10 and on the compensation term uw.
  • the coefficients K i_ui and K p_ui may be determined by placement of poles of a closed-loop system according to a method of control by full-state feedback, such as is, for example, addressed in the following link: https://fr.wikipedia.org/wiki/Commande_par_retour_d %27% C3% A9tat
  • the sub-system 101 for adjusting the control law of the aircraft 10 calculates a feedback aimed at cancelling the impact of the wind V on the aircraft 10 .
  • the modelling of the closed-loop system comprises a first term which depends on the setpoint, typically the controlled vertical load factor Nzc, and a second term which depends on the wind V, called “sensitivity function” in control theory.
  • the expression of this sensitivity function may be obtained analytically.
  • the sensitivity function is expressed in the form of a numerator and a denominator.
  • the denominator is for example determined by a conventional method by placement of poles, and the sub-system 101 for adjusting the control law of the aircraft 10 tries to cancel the numerator in order to cancel the effect of the wind V.
  • a step 205 the system 100 for controlling the flight control surfaces of the aircraft 10 controls the aircraft 10 in flight with the adjusted control law for flight control surfaces u a obtained at the step 204 .
  • the adjusted control law for flight control surfaces u a obtained at the step 204 (which takes the wind into account) rather than the control law for the flight control surfaces ui obtained at the step 201 (which does not take the wind into account)
  • the impact of the wind on the aircraft 10 is thus minimized, which reduces the impact of the wind on the flight path of the aircraft and/or on the fatigue of the structure of the aircraft.
  • FIG. 3 illustrates schematically one example of a hardware platform 300 , in the form of electronic circuitry, which is designed and configured for implementing all or part of the system 100 for controlling the flight control surfaces of the aircraft 10 , and more particularly the sub-system 101 for adjusting the control law of the aircraft 10 .
  • the hardware platform thus comprises, linked via a communications bus 310 : a processor or CPU (Central Processing Unit) 301 ; a volatile memory RAM (Random Access Memory) 302 ; a non-volatile memory 303 , for example of the ROM (Read-Only Memory) type or EEPROM (Electrically-Erasable Programmable ROM); a storage unit 304 , such as an HDD (Hard Disk Drive), or a storage medium reader, such as an SD (Secure Digital) card reader; and an interface manager I/f 305 .
  • a processor or CPU Central Processing Unit
  • RAM Random Access Memory
  • non-volatile memory 303 for example of the ROM (Read-Only Memory) type or EEPROM (Electrically-Erasable Programmable ROM)
  • a storage unit 304 such as an HDD (Hard Disk Drive), or a storage medium reader, such as an SD (Secure Digital) card reader
  • an interface manager I/f 305 .
  • the interface manager I/f 305 allows an interaction with one or more devices of the aircraft 10 , more particularly avionics equipment of the aircraft 10 , in order to receive information useful for the estimation of the wind and for applying the adjusted control law to the control of the flight control surfaces of the aircraft 10 .
  • All or part of the steps and operations described herein may thus be implemented in software form by execution of a set of instructions by a programmable machine, for example a processor of the DSP (Digital Signal Processor) type or a microcontroller, or be implemented in hardware form by a machine or a dedicated chip or a chipset, for example an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit) component.
  • a programmable machine for example a processor of the DSP (Digital Signal Processor) type or a microcontroller
  • DSP Digital Signal Processor
  • FPGA Field Programmable Gate Array
  • ASIC Application Specific Integrated Circuit

Landscapes

  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Security & Cryptography (AREA)
  • Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)

Abstract

A system for controlling aircraft flight control surfaces implements a method including: obtaining a control law for the flight control surfaces as a function of flight controls of the aircraft; obtaining measurements of ground speed, true speed, roll angle, pitch angle, angle of attack, sideslip angle and slope angle; performing an estimation of the wind in three dimensions using the measurements obtained; performing an adjustment of the control law for the flight control surfaces, to counter the estimated wind effect and to obtain an adjusted control law for the flight control surfaces, by adding, to the control law, a term for wind compensation comprising a term proportional to the derivative of the wind estimation; and controlling the aircraft by applying the adjusted control law. Thus, the impact of the wind on the aircraft is reduced by digital processing and automatic adjustment of the control of the flight control surfaces.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the benefit of the French patent application No. 2208631 filed on Aug. 29, 2022, the entire disclosures of which are incorporated herein by way of reference.
FIELD OF THE INVENTION
The present invention relates to the field of the adjustment of aircraft controls in order to take into account an impact of wind on the aircraft in flight.
BACKGROUND OF THE INVENTION
When an aircraft is in flight, the wind leads to deviations of the flight path of the aircraft with respect to a desired flight path, referred to as reference flight path. In addition, notably due to turbulence, the wind has an impact on the flight path of the aircraft, or on the angular velocity of the aircraft, or on the attitude of the aircraft, or an impact of fatigue on the structure of the aircraft or other elements of the aircraft.
On modern aircraft, the flight controls are digital electrical flight controls, which allows the flight control surfaces of these aircraft to be adjusted by digital processing.
It is accordingly desirable to provide a solution which allows, automatically and by digital processing, the impact of the wind on the flight path of the aircraft and/or on the fatigue of the structure of the aircraft to be reduced.
SUMMARY OF THE INVENTION
For this purpose, a method is provided for controlling the flight control surfaces of an aircraft, the method being implemented by a system for controlling the flight control surfaces of the aircraft in the form of electronic circuitry and comprising the following steps: obtaining a control law for the flight control surfaces ui as a function of flight controls of the aircraft; obtaining measurements of ground speed VGND of the aircraft, of true speed VTAS of the aircraft, of roll angle φ of the aircraft, of pitch angle θ of the aircraft, of angle of attack α of the aircraft, of sideslip angle β of the aircraft, and of slope angle γ of the aircraft; performing an estimation of the wind V in three dimensions using the measurements obtained; performing an adjustment of the control law for the flight control surfaces ui, in order to counter the estimated effect of the wind, and thus obtain an adjusted control law for the flight control surfaces ua, by adding, to the control law for the flight control surfaces ui, a term for compensation of the wind uw comprising a term proportional to the derivative {dot over (V)} of the wind estimation V; and controlling the aircraft by applying the adjusted control law ua. Thus, the impact of the wind on the aircraft is reduced by digital processing and automatic adjustment of the control of the flight control surfaces of the aircraft.
In one particular embodiment:
u w =−inv(CB)CM{dot over (V)}
where C,B and M are matrices defined by
{dot over (x)}=Ax+B(u w +u i)+M{dot over (V)}
with:
y = Cx = C s x .
where:
    • x represents the current state of the aircraft in the form of vectors, defined by aeronautical parameters having an influence on the stability of the aircraft,
    • {dot over (x)} represents the state of the aircraft after application of the control law for the flight control surfaces, here the control law for the flight control surfaces ua,
    • y represents excursions of the aircraft on which the impact of the wind is to be minimized,
    • A, B and C represent state matrices of the aircraft reproducing the dynamic behavior of its movement,
    • s represents the Laplace operator, and
    • M is a transfer matrix for the wind V.
In one particular embodiment, the adjusted control law for the flight control surfaces ua is obtained by further adding, to the control law for the flight control surfaces ui, a term proportional to the integral of the derivative {dot over (V)} of the wind estimation V.
More particularly, the aircraft is modelled with a filter of the first order of constant τ, and
{ K i = - 1 K = - τ
where Ki is a multiplier coefficient of the proportional term of the integral of the derivative {dot over (V)} of the wind estimation V and where K is a multiplier coefficient of the term proportional to the derivative {dot over (V)} of the wind estimation V.
In one particular embodiment, the adjusted control law for the flight control surfaces ua is obtained by further adding, to the control law for the flight control surfaces ui, a term proportional to the second derivative {umlaut over (V)} of the wind estimation V.
More particularly, the aircraft is modelled with a filter of the second order having a damping ξ0 and an angular frequency ω0, and:
{ K i = - 1 K = - 2 ξ 0 ω 0 K d = - 1 ω 0 2
where Ki is a multiplier coefficient of the term proportional to the integral of the derivative {dot over (V)} of the wind estimation V, where K is a multiplier coefficient of the term proportional to the derivative {dot over (V)} of the wind estimation V and where Kd is a multiplier coefficient of the term proportional to the second derivative {umlaut over (V)} of the wind estimation V.
A computer program product is also provided, comprising instructions causing execution, by a processor, of the method according to any one of the embodiments described hereinabove, when said instructions are executed by the processor. A storage medium is also provided, storing a computer program comprising instructions causing execution, by a processor, of the method according to any one of the embodiments described hereinabove, when said instructions are read and executed by the processor.
A system for controlling flight control surfaces of an aircraft is also provided in the form of electronic circuitry configured for implementing the following steps: obtaining a control law for the flight control surfaces ui as a function of flight controls of the aircraft; obtaining measurements of ground speed VGND of the aircraft, of true speed VTAS of the aircraft, of roll angle φ of the aircraft, of pitch angle θ of the aircraft, of angle of attack α of the aircraft, of sideslip angle β of the aircraft, and of slope angle γ of the aircraft; performing an estimation of the wind V in three dimensions using the measurements obtained; performing an adjustment of the control law for the flight control surfaces ui, in order to counter the effect of the estimated wind, and thus to obtain an adjusted control law for the flight control surfaces ua, by adding, to the control law for the flight control surfaces ui, a term for compensation of the wind uw comprising a term proportional to the derivative {dot over (V)} of the wind estimation V; and controlling the aircraft by applying the adjusted control law ua.
An aircraft is also provided comprising a control system for flight control surfaces such as described hereinabove.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the invention mentioned hereinabove, together with others, will become more clearly apparent upon reading the following description of at least one exemplary embodiment, the said description being presented in relation with the appended drawings, amongst which:
FIG. 1 illustrates schematically, as a top view, an aircraft equipped with a system for controlling the flight control surfaces of the aircraft comprising a sub-system for adjusting a control law of the aircraft;
FIG. 2 illustrates schematically a flow diagram of a method for controlling the aircraft in flight aimed at reducing the impact of the wind on the aircraft; and
FIG. 3 illustrates schematically one example of a hardware platform designed and configured for implementing the sub-system for adjusting a control law of the aircraft.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 thus illustrates schematically, as a top view, an aircraft 10. The aircraft 10 comprises a system 100 for controlling the flight control surfaces of the aircraft 10 (elevators, ailerons, rudder). The system 100 applies a control law for the flight control surfaces (deflection commands) of the aircraft 10 as a function of flight controls of the aircraft 10.
The system 100 for controlling the flight control surfaces of the aircraft 10 comprises a sub-system 101 for adjusting the control law of the aircraft 10 as a function of an estimation of the wind to which the aircraft 10 is subjected in flight.
Conventionally, the aircraft 10 comprises sensors (not shown in FIG. 1 ) and electronic control circuitry, designed and configured for supplying measurements of speed and of orientation of the aircraft 10. By virtue of these measurements, the sub-system 101 for adjusting the control law of the aircraft 10 is able to carry out an estimation of the wind in three dimensions, in a right orthonormal reference frame (xb, yb, zb) fixed with respect to the center of gravity of the aircraft 10 (with xb oriented towards the front of the aircraft 10 and yb oriented towards the left of the aircraft 10), in the following manner:
V = [ - V GND tan ( γ ) - V TAS ( sin ( θ ) cos ( β ) cos ( α ) - cos ( θ ) cos ( φ ) cos ( β ) sin ( α ) - sin ( β ) cos ( θ ) sin ( φ ) ) ) ) V GND tan ( γ ) - V TAS ( sin ( θ ) cos ( β ) cos ( α ) - cos ( θ ) cos ( φ ) cos ( β ) sin ( α ) + sin ( β ) cos ( θ ) sin ( φ ) ) ) ) ] [ MATH . 1 ]
where:
    • VGND represents the ground speed (horizontal speed of the aircraft 10 with respect to the surface of the Earth),
    • VTAS represents the true speed of the aircraft 10 (speed of the aircraft with respect to the mass of air through which the aircraft is flying),
    • φ represents the roll angle of the aircraft 10, such as supplied by the IRS (Inertial Reference System),
    • θ represents the pitch angle of the aircraft 10, such as supplied by the inertial reference system IRS,
    • α represents the angle of attack of the aircraft 10, such as supplied by the ADIRS (Air Data Inertial Reference System),
    • β represents the sideslip angle of the aircraft 10, such as supplied by the air data inertial reference system ADIRS, and
    • γ represents the slope angle of the aircraft 10, such as supplied by the ADIRS (Air Data Inertial Reference System).
As disclosed hereinafter, the sub-system 101 for adjusting the control law of the aircraft 10 comprises electronic circuitry designed and configured for carrying out a real-time estimation of the wind such as expressed hereinabove, in order to adjust a control law for flight control surfaces so as to reduce the impact of the wind on the aircraft 10.
FIG. 2 illustrates schematically a method for controlling the aircraft 10 in flight aimed at reducing the impact of the wind on the aircraft 10.
In a step 201, the system 100 for controlling the flight control surfaces of the aircraft 10 obtains a control law for the flight control surfaces ui as a function of flight controls of the aircraft 10. The flight controls are actuated by the pilot, or by an autopilot system, for maneuvering the aircraft 10 in flight. The control law for the flight control surfaces ui, obtained at the step 201, does not take into account the estimation of the wind.
In a step 202, the system 100 for controlling the flight control surfaces of the aircraft 10 obtains measurements of speed and of orientation of the aircraft 10 useful for the estimation of the wind, in real time. More particularly, the system 100 for controlling the flight control surfaces of the aircraft 10 obtains measurements of the ground speed VGND and of the true speed VTAS. The system 100 for controlling the flight control surfaces of the aircraft 10 further obtains the roll angle φ and the pitch angle θ, together with the angle of attack α, the sideslip angle β and the slope angle γ.
In a step 203, the sub-system 101 for adjusting the control law of the aircraft 10 carries out an estimation of the wind, as already described hereinabove. The sub-system 101 for adjusting the control law of the aircraft 10 tracks the estimation of the wind over time.
In a step 204, the sub-system 101 for adjusting the control law of the aircraft 10 carries out an adjustment of the control law for the flight control surfaces ui obtained at the step 201, in order to counter the effect of the wind such as estimated at the step 203, and thus obtains an adjusted control law for the flight control surfaces ua.
In order to obtain the adjusted control law for the flight control surfaces ua, the sub-system 101 for adjusting the control law of the aircraft 10 adds, to the control law for the flight control surfaces ui obtained at the step 201, a term for compensation of the wind uw. More precisely, the term for compensation of the wind uw comprises a term proportional to the derivative V of the wind estimation V from the step 203, and thus:
u a =u i +u w =u i +K{dot over (V)}
where K is a predetermined coefficient.
In one particular embodiment, the term for compensation of the wind uw further comprises a term proportional to the integral of the derivative {dot over (V)} of the wind estimation V from the step 203, and thus:
u a =u i +u w =u i +K{dot over (V)}+K i ∫{dot over (V)}
where Ki is a predetermined coefficient.
In one particular embodiment, the term for compensation of the wind uw further comprises a term proportional to the second derivative V of the wind estimation V from the step 203, and thus:
u a =u i +u w =u i +K{dot over (V)}+K i ∫{dot over (V)}+K d {umlaut over (V)}
where Kd is a predetermined coefficient.
First Method
In a first method, the aircraft 10 is modelled by a representation of states defined, for a non-rigid aircraft aero-elastic model (taking into account elastic deformations due to the coupling between structural modes and aerodynamic forces), by:
x . = Ax + Bu i y = Cx = C s x .
where:
    • x represents, in the form of vectors, the current state of the aircraft 10, defined by aeronautical parameters having an influence on the stability of the aircraft 10, typically [α q VTAS θ] on the longitudinal axis xb and [β r p φ] jointly on the yaw and roll axes, where q represents the pitching speed, r represents the yawing speed and p represents the rolling speed,
    • {dot over (x)} represents the state of the aircraft 10 after application of the control law for the flight control surfaces, here the control law for the flight control surfaces ui,
    • y represents excursions of the aircraft 10 on which the impact of the wind is to be minimized (for example, an angular velocity, or an attitude, or a structural fatigue criterion or for any modellable element of the aircraft 10, etc.),
    • A, B and C represent matrices of state of the aircraft 10 reproducing the dynamic behavior of its movement.
    • s represents the Laplace operator.
In summary, the new state {dot over (x)} of the aircraft 10 obtained by applying the control law for the flight control surfaces ui depends on the current state x of the aircraft 10 and on the control law for the flight control surfaces ui.
The matrices A, B and C are obtained by applying the equations of mechanics for the flight of the aircraft 10. Such a modelling is for example described in “The dynamics of flight” by Jean-Luc Boiffier. In this work, the matrices A, B and C are obtained from functions F(X,U) as described on page 135 and the following pages. A linearization of the matrices is subsequently carried out, as described on page 158. Such a modelling is also for example described in section 2.2 of the document “Méthodologie de conception de lois de pilotage multiobjectifs autoséquencées pour un avion de transport civil souple” (“Methodology for designing autosequenced multi-objective flight control laws for a non-rigid commercial transport airplane”), José TORRALBA, 2011, ONERA, University of Toulouse.
Thus, in order to take into account the effect of the wind, it is possible to derive the model in the following manner:
{dot over (x)}=Ax+Bu a +M{dot over (V)}=Ax+B(u w +u i)+M{dot over (V)}
still with:
y = Cx = C s x .
where M is a transfer matrix for the wind, in other words a matrix for estimating the effect of the wind on the states of the model.
The matrix M is obtained either analytically or by simulation, for example by simulation with a complete aircraft simulator, where, by knowing x, {dot over (x)}, and ui, and the derivative of the wind {dot over (V)}, it is possible to accordingly deduce the content of the matrix M by calculation.
In summary, the new state {dot over (x)} of the aircraft 10 associated with the compensation term uw depends on the current state x of the aircraft 10 and on the compensation term uw.
In order to cancel the effect of the wind on the fatigue of the structure of the aircraft 10, the following equation must be validated:
CBu w +CM{dot over (V)}=0
Accordingly, in order to compensate the effect of the wind on the fatigue of the structure of the aircraft 10, the sub-system 101 for adjusting the control law of the aircraft 10 calculates the term for compensation of the wind uW in the following manner:
u w =−inv(CB)CM {dot over (V)}
Thus, in the embodiment where
u a =u i +u w =u i +K{dot over (V)}
this leads to
K=−inv(CB)CM
Second Method
In a second method, the aircraft 10 is modelled by a filter of the first order, with a constant τ, or of the second order, with a damping ξ0 and an angular frequency ω0. The constant r, just like the damping ξ0 and the angular frequency ω0, are dynamic characteristics obtained by virtue of a simulator. The first or second order corresponds to more or less accurate modelling of the aircraft 10. The second order will be more accurate than the first order. The choice between first order and second order is made depending on a desired accuracy.
It is possible to model the adjusted control law for the flight control surfaces ua in the following manner:
u a = K i _ ui s ( y c - y mes ) + K p _ ui y mes + K i δ y + K δ . y + K d δ ¨ y
where:
    • yc represents the setpoint for the closed-loop control (for example, the attitude or the pitching angular velocity)
    • ymes represents the measurement of the parameter being controlled, such as the attitude or the pitching angular velocity. It should be noted that ymes comprises the contribution of the pilot to the parameter being controlled, together with the contribution of the wind V.
    • Ki_ui and Kp_ui are predetermined coefficients relating to the control law for the flight control surfaces ui obtained at the step 201, such that:
u i = K i _ ui s
The coefficients Ki_ui and Kp_ui may be determined by placement of poles of a closed-loop system according to a method of control by full-state feedback, such as is, for example, addressed in the following link: https://fr.wikipedia.org/wiki/Commande_par_retour_d %27% C3% A9tat
By considering the control of the flight control surfaces of the aircraft 10 as a closed-loop system, the sub-system 101 for adjusting the control law of the aircraft 10 calculates a feedback aimed at cancelling the impact of the wind V on the aircraft 10. The modelling of the closed-loop system comprises a first term which depends on the setpoint, typically the controlled vertical load factor Nzc, and a second term which depends on the wind V, called “sensitivity function” in control theory. The expression of this sensitivity function may be obtained analytically. The sensitivity function is expressed in the form of a numerator and a denominator. The denominator is for example determined by a conventional method by placement of poles, and the sub-system 101 for adjusting the control law of the aircraft 10 tries to cancel the numerator in order to cancel the effect of the wind V.
Thus, in the embodiment where
u a =u i +u w =u i +K{dot over (V)}+K i ∫{dot over (V)}+K d {umlaut over (V)}
it turns out that, with a filter of the first order, the coefficients are fixed in the following manner:
{ K i = - 1 K = - τ K d = 0
which cancels the term proportional to the second derivative V of the wind estimation V,
and, with a filter of the second order, the coefficients are fixed in the following manner:
{ K i = - 1 K = - 2 ξ 0 ω 0 K d = - 1 ω 0 2
In a step 205, the system 100 for controlling the flight control surfaces of the aircraft 10 controls the aircraft 10 in flight with the adjusted control law for flight control surfaces ua obtained at the step 204. By applying the adjusted control law for flight control surfaces ua obtained at the step 204 (which takes the wind into account) rather than the control law for the flight control surfaces ui obtained at the step 201 (which does not take the wind into account), the impact of the wind on the aircraft 10 is thus minimized, which reduces the impact of the wind on the flight path of the aircraft and/or on the fatigue of the structure of the aircraft.
FIG. 3 illustrates schematically one example of a hardware platform 300, in the form of electronic circuitry, which is designed and configured for implementing all or part of the system 100 for controlling the flight control surfaces of the aircraft 10, and more particularly the sub-system 101 for adjusting the control law of the aircraft 10.
The hardware platform thus comprises, linked via a communications bus 310: a processor or CPU (Central Processing Unit) 301; a volatile memory RAM (Random Access Memory) 302; a non-volatile memory 303, for example of the ROM (Read-Only Memory) type or EEPROM (Electrically-Erasable Programmable ROM); a storage unit 304, such as an HDD (Hard Disk Drive), or a storage medium reader, such as an SD (Secure Digital) card reader; and an interface manager I/f 305.
The interface manager I/f 305 allows an interaction with one or more devices of the aircraft 10, more particularly avionics equipment of the aircraft 10, in order to receive information useful for the estimation of the wind and for applying the adjusted control law to the control of the flight control surfaces of the aircraft 10.
The processor 301 is capable of executing instructions loaded into the volatile memory 302 from the non-volatile memory 303, from an external memory, from a storage medium (such as an SD card), or from a communications network. When the hardware platform is powered up, the processor 301 is capable of reading instructions from the volatile memory 302 and of executing them. These instructions form a computer program causing the implementation, by the processor 301, of all or part of the steps and operations described here.
All or part of the steps and operations described herein may thus be implemented in software form by execution of a set of instructions by a programmable machine, for example a processor of the DSP (Digital Signal Processor) type or a microcontroller, or be implemented in hardware form by a machine or a dedicated chip or a chipset, for example an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit) component. Generally speaking, the hardware platform comprises electronic circuitry designed and configured for implementing the operations and steps described herein.
While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.

Claims (10)

The invention claimed is:
1. A method for controlling flight control surfaces of an aircraft, the method being carried out by a system for controlling the flight control surfaces of the aircraft formed of electronic circuitry and comprising the following steps:
obtaining a control law for the flight control surfaces as a function of flight controls of the aircraft;
obtaining measurements of ground speed of the aircraft, of true speed of the aircraft, of roll angle of the aircraft, of pitch angle of the aircraft, of angle of attack of the aircraft, of sideslip angle of the aircraft, and of slope angle of the aircraft;
estimating a velocity of wind in three dimensions using the measurements obtained;
performing an adjustment of the control law for the flight control surfaces, in order to counter an estimated effect of the wind, and thus obtain an adjusted control law for the flight control surfaces by adding, to the control law for the flight control surfaces, a term for compensation of the wind comprising a term proportional to a derivative of the wind estimation; and
controlling the aircraft by adjusting the flight controls to modify the flight control surfaces in response to the adjusted control law.
2. The method according to claim 1, wherein:

u w =−inv(CB)CM{dot over (V)}

where C,B and M are matrices defined by

{dot over (x)}=Ax+B(u w +u i)+M{dot over (V)}
with:
y = Cx = C s x .
where
uw represents the term for compensation of the wind estimation,
ui represents the control law,
{dot over (V)} represents the term proportional to a derivative of the wind estimation,
x represents, as vectors, a current state of the aircraft, defined by aeronautical parameters having an influence on a stability of the aircraft,
{dot over (x)} represents the state of the aircraft after application of the control law for the flight control surfaces, here the control law for the flight control surfaces,
y represents excursions of the aircraft on which an impact of the wind is to be minimized,
A, B and C represent matrices of state of the aircraft reproducing a dynamic behavior of its movement,
s represents a Laplace operator, and
M is a transfer matrix for the wind V.
3. The method according to claim 1, wherein the adjusted control law for the flight control surfaces is obtained by further adding, to the control law for the flight control surfaces, a term proportional to an integral of a derivative of the wind estimation.
4. The method according to claim 3, wherein the aircraft is modelled with a filter of a first order of constant τ, and wherein
{ K i = - 1 K = - τ
where Ki is a multiplier coefficient of the term proportional to the integral of the derivative of the wind estimation and where K is a multiplier coefficient of the term proportional to the derivative of the wind estimation.
5. The method according to claim 4, wherein the aircraft is modelled with a filter of a second order having a damping ξ0 and an angular frequency ω0 and wherein:
{ K i = - 1 K = - 2 ξ 0 ω 0 K d = - 1 ω 0 2
where Ki is a multiplier coefficient of the term proportional to the integral of the derivative of the wind estimation, where K is a multiplier coefficient of the term proportional to the derivative {dot over (V)} of the wind estimation V and where Kd is a multiplier coefficient of the term proportional to a second derivative of the wind estimation.
6. The method according to claim 3, wherein the adjusted control law for the flight control surfaces is obtained by further adding, to the control law for the flight control surfaces, a term proportional to a second derivative of the wind estimation.
7. A computing device having a non-volatile memory containing a computer program product, comprising instructions causing an execution, by a processor, of the method according to claim 1, when said instructions are executed by the processor.
8. A non-transitory memory storage medium, storing a computer program comprising instructions causing an execution, by a processor, of the method according to claim 1, when said instructions are read and executed by the processor.
9. A system for controlling flight control surfaces of an aircraft formed of electronic circuitry configured for implementing the following steps:
obtaining a control law for the flight control surfaces as a function of flight controls of the aircraft;
obtaining measurements of ground speed of the aircraft, of true speed of the aircraft, of roll angle of the aircraft, of pitch angle of the aircraft, of angle of attack of the aircraft, of sideslip angle of the aircraft, and of slope angle of the aircraft;
the electronic circuitry being configured for implementing the following steps:
estimating a velocity of wind in three dimensions using the measurements obtained;
performing an adjustment of the control law for the flight control surfaces, in order to counter an estimated effect of the wind, and thus obtain an adjusted control law for the flight control surfaces, by adding, to the control law for the flight control surfaces, a term for compensation of the wind comprising a term proportional to a derivative of the wind estimation; and
controlling the aircraft by adjusting the flight controls to modify the flight control surfaces in response to the adjusted control law.
10. An aircraft comprising a control system of flight control surfaces according to claim 9.
US18/455,884 2022-08-29 2023-08-25 Method for adjusting aircraft controls Active 2043-10-18 US12429885B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR2208631A FR3139208A1 (en) 2022-08-29 2022-08-29 METHOD FOR ADJUSTING AIRCRAFT CONTROLS
FR2208631 2022-08-29

Publications (2)

Publication Number Publication Date
US20240077889A1 US20240077889A1 (en) 2024-03-07
US12429885B2 true US12429885B2 (en) 2025-09-30

Family

ID=84569028

Family Applications (1)

Application Number Title Priority Date Filing Date
US18/455,884 Active 2043-10-18 US12429885B2 (en) 2022-08-29 2023-08-25 Method for adjusting aircraft controls

Country Status (3)

Country Link
US (1) US12429885B2 (en)
EP (1) EP4332001B1 (en)
FR (1) FR3139208A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3161040A1 (en) * 2024-04-05 2025-10-10 Airbus Operations METHOD AND SYSTEM FOR REDUCING AERODYNAMIC LOADS EXERCISED ON AN AIRCRAFT BY ATMOSPHERIC TURBULENCE.
CN119557548B (en) * 2024-11-30 2025-10-14 西北工业大学 A specified time increment control method for aircraft airflow angle under multiple fault disturbances
CN119882811B (en) * 2025-03-27 2025-05-30 安徽大学 An energy-saving and wind-resistant flight control method for unmanned aerial vehicles based on wind energy utilization

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080046137A1 (en) * 2004-10-08 2008-02-21 Shue Shyhpyng J Control System for Automatic Flight in Windshear Conditions
RU2377159C1 (en) * 2005-10-11 2009-12-27 Эрбюс Франс Method and device to control vertical turbulence on aircraft
US20160023776A1 (en) 2014-07-23 2016-01-28 Honeywell International Inc. Systems and methods for airspeed estimation using actuation signals
RU2713585C1 (en) * 2019-01-29 2020-02-05 Акционерное общество "Раменское приборостроительное конструкторское бюро" Method of forming air-speed parameters of a manoeuvrable object
US11029709B1 (en) * 2017-12-28 2021-06-08 United States Of America As Represented By The Administrator Of Nasa Adaptive wind estimation, trajectory generation, and flight control for aerial systems using motion data

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080046137A1 (en) * 2004-10-08 2008-02-21 Shue Shyhpyng J Control System for Automatic Flight in Windshear Conditions
RU2377159C1 (en) * 2005-10-11 2009-12-27 Эрбюс Франс Method and device to control vertical turbulence on aircraft
US20160023776A1 (en) 2014-07-23 2016-01-28 Honeywell International Inc. Systems and methods for airspeed estimation using actuation signals
US11029709B1 (en) * 2017-12-28 2021-06-08 United States Of America As Represented By The Administrator Of Nasa Adaptive wind estimation, trajectory generation, and flight control for aerial systems using motion data
RU2713585C1 (en) * 2019-01-29 2020-02-05 Акционерное общество "Раменское приборостроительное конструкторское бюро" Method of forming air-speed parameters of a manoeuvrable object

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
Espacenet machine translation of RU2377159C1 Kolomer (Year: 2009). *
Espacenet machine translation of RU2713585C1 Manokhin (Year: 2020). *
French Search Report for corresponding French Patent Application No. 2208631 dated Feb. 19, 2023; priority document.
G. Perozzi et al., "On Sliding Mode Control Design for UAV Using Realistic Aerodynamic Coefficients" 2017 IEEE 56th Annual Conference on Decision and Control (CDC), IEEE, Dec. 12, 2017; pp. 5403-5408.
Jean-Luc Boiffier, "The Dynamics of Flight".

Also Published As

Publication number Publication date
EP4332001A1 (en) 2024-03-06
US20240077889A1 (en) 2024-03-07
FR3139208A1 (en) 2024-03-01
EP4332001B1 (en) 2025-03-19

Similar Documents

Publication Publication Date Title
US12429885B2 (en) Method for adjusting aircraft controls
CN112578802B (en) Aircraft control system and method using sliding mode control and feedback linearization
EP3635501B1 (en) Method and controller for controlling an aircraft by improved direct lift control
Chowdhary et al. Guidance and control of airplanes under actuator failures and severe structural damage
US6757570B1 (en) System and method for adaptive control of uncertain nonlinear processes
CN101667036B (en) Control system for automatic flight and windshear conditions
JP4570842B2 (en) Method, apparatus and design procedure for controlling a multiple input multiple output (MIMO) parameter dependent system using feedback LTI
Paw et al. Development and application of an integrated framework for small UAV flight control development
US11460865B2 (en) Method and system for longitudinal control of aircraft
Yavrucuk et al. Envelope protection for autonomous unmanned aerial vehicles
Wei et al. Mitigating ground effect on mini quadcopters with model reference adaptive control: P. Wei et al.
CN113759718B (en) An adaptive control method for aircraft wing damage
Kokunko et al. Synthesis of a tracking system with restrictions on UAV state variables
US12498735B1 (en) Methods for attitude control of quadrotor unmanned aerial vehicle (UAV)
Dadkhah et al. Control system design and evaluation for robust autonomous rotorcraft guidance
Wasim et al. Robust design of sliding mode control for airship trajectory tracking with uncertainty and disturbance estimation
Lee et al. Fault-tolerant control for aircraft with structural damage using sparse online gaussian process regression
Rauf et al. Design and analysis of stability and control for a small unmanned aerial vehicle: MN Rauf et al.
Surmann et al. Gain design for an indi-based flight control algorithm for a conceptual lift-to-cruise vehicle
Flanagan et al. Model Based Roll Controller Tuning and Analysis for Small UAS in Turbulent Environments
KR102093746B1 (en) Control method of aircraft based on angular acceleration information
Hartley Predictive control with parameter adaptation to achieve α-protection in the RECONFIGURE benchmark in the presence of icing
Weiser et al. In-flight validation of a robust flight controller featuring anti-windup compensation
KR101461489B1 (en) Method of model following control for a rotorcraft and system using the same
Efremov et al. Influence of the order of vehicle motion equations in the implementation of an adaptive flight control system with the real time identification of controlled element dynamics parameters

Legal Events

Date Code Title Description
FEPP Fee payment procedure

Free format text: ENTITY STATUS SET TO UNDISCOUNTED (ORIGINAL EVENT CODE: BIG.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

AS Assignment

Owner name: AIRBUS OPERATIONS SAS, FRANCE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:DELLANOY, STEPHANE;TORRALBA, JOSE;SIGNING DATES FROM 20231211 TO 20240314;REEL/FRAME:066844/0703

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS

STPP Information on status: patent application and granting procedure in general

Free format text: PUBLICATIONS -- ISSUE FEE PAYMENT RECEIVED

STPP Information on status: patent application and granting procedure in general

Free format text: PUBLICATIONS -- ISSUE FEE PAYMENT VERIFIED

STCF Information on status: patent grant

Free format text: PATENTED CASE